# NTSB Safety Recommendation P-94-003 **Citation:** P-94-003 **Type / status:** guidance / guidance **Agency:** National Transportation Safety Board **Effective:** 1994-04-22 **Published:** 1994-04-22 THE NTSB RECOMMENDS THAT THE NEW JERSEY NATURAL GAS COMPANY: INSTALL EXCESS FLOW VALVES ON NEW AND RENEWED SINGLE-CUSTOMER RESIDENTIAL HIGH-PRESSURE SERVICE LINES THAT HAVE OPERATING CONDITIONS COMPATIBLE WITH AVAILABLE EXCESS FLOW VALVES. ## Document text NTSB safety recommendation P-94-003. THE NTSB RECOMMENDS THAT THE NEW JERSEY NATURAL GAS COMPANY: INSTALL EXCESS FLOW VALVES ON NEW AND RENEWED SINGLE-CUSTOMER RESIDENTIAL HIGH-PRESSURE SERVICE LINES THAT HAVE OPERATING CONDITIONS COMPATIBLE WITH AVAILABLE EXCESS FLOW VALVES. Priority: CLASS II Overall Status: Closed - Acceptable Action Issued Date: 1994-04-22 Adopted Date: 1994-04-15 Overall Date Closed: 1995-08-01 Synopsis: ABOUT 11:35 A.M. ON JUNE 9, 1993, A CINDERBLOCK DUPLEX AT 634 CLIFFWOOD AVENUE IN CLIFFWOOD BEACH, NEW JERSEY, EXPLODED AS A NEW JERSEY NATURAL GAS COMPANY (NJNG) CONTRACTOR WAS TRENCHING IN FRONT OF THE BUILDING. THE EXPLOSION KILLED 3 RESIDENTS OF THE DUPLEX AND SERIOUSLY INJURED 3 OTHERS. Probable Cause: None Keywords: Excess Flow Valves Ntsbnumber: DCA93FP008 Report Number: None Addressee Name: New Jersey Natural Gas Company Addressee Status: Closed - Acceptable Action Addressee Date Closed: 1995-08-01 Addressee Acronym: NJNG Addressee Organization Type: P-Private Industry Communication Date: 1995-08-01 Communication Type: Official Correspondence Communication Contents: THE BOARD AGREES THAT THE CURRENT EFV PROGRAM WOULD NOT HAVE PREVENTED THE 6/9/93 ACCIDENT, BUT HAD AN EFV BEEN IN THE SERVICE LINE AT THE TIME OF THE ACCIDENT, IT SHOULD HAVE ACTIVATED, THEREBY MINIMIZING POTENTIAL LOSSES. THE NJNG'S NEW POLICY ON INSTALLING EFVS IS CONSISTENT WITH THE RECOMMENDED ACTION, & P-94-3 IS, THEREFORE, CLASSIFIED "CLOSED--ACCEPTED ACTION." Addressee Acronym: NJNG Addressee Organization Type: P-Private Industry Communication Date: 1995-06-07 Communication Type: Official Correspondence Communication Contents: NJNG COMPLETED PHASE-IN THE EFV PROGRAM IN APRIL, 1995. NJNG INSTALLS EXCESS FLOW VALVES ON ALL NEW & RENEWED HIGH PRESSURE RESIDENTIAL GAS SYSTEMS SERVICE OPERATING AT A PRESSURE GREATER THAN 10M PSIG. EXCESS FLOW VALVES WILL NOT BE INSTALLED ON RESIDENTIAL SERVICES OPERATING AT A VOLUME IN EXCESS OF 400 CFH. NJNG HAS REVISED ITS CONSTRUCTION (STANDARDS) MANUAL TO INCORPORATE THIS PROVISION. WHILE NJNG BELIEVES THAT INSTALLING EXCESS FLOW VALVES ENHANCES THE SAFETY OF OUR SYSTEM, THIS PROGRAM WOULD NOT HAVE PREVENTED THE EXPLOSION AT 634 CLIFFWOOD AVENUE ON 6/9/93. THE EXISTENCE OF THE LINE DAMAGED THAT DAY WAS NOT KNOWN TO NJNG. IT IS MOST LIKELY THAT THE LINE WAS INSTALLED BEFORE WE PURCHASED THE FRANCHISE IN THAT AREA AND BEFORE EXCESS FLOW VALVES WERE IN GENERAL USE. ## Provenance - Official: Yes - Source: - Source ID: `ntsb-pipeline` - SHA-256: `d6a5ae091db836ceda323727a7aa8cf7cf7d19fe4d96ab4c1d29c32bf0c2d0e2` - Retrieved: 2026-08-20T04:57:24.741Z - Exported: 2026-08-23T18:59:36.723Z - Document slug: `ntsb-recommendation-p-94-003` ### Source metadata ```json { "recordKind": "ntsb_safety_recommendation", "safetyRecommendationNumber": "P-94-003", "recommendationMode": "Pipeline", "topicMode": "Pipeline", "ntsbNumber": "DCA93FP008", "priority": "CLASS II", "overallStatus": "Closed - Acceptable Action", "overallStatusAcronym": "CAA", "overallDateClosed": "1995-08-01", "lastModifiedDate": "2026-03-19", "reportNumber": "None", "reportUrl": null, "transmittalLetterUrl": "http://www.ntsb.gov/safety/safety-recs/recletters/P94_1_3.pdf", "addressees": [ { "addresseeName": "New Jersey Natural Gas Company", "addresseeStatusAcronym": "CAA", "addresseeStatus": "Closed - Acceptable Action", "addresseeDateClosed": "1995-08-01", "addresseeDetails": [ { "addresseeAcronym": "NJNG", "addresseeOrganizationType": "P-Private Industry", "isFromNtsb": true, "communicationDate": "1995-08-01", "communicationType": "Official Correspondence", "communicationContents": "THE BOARD AGREES THAT THE CURRENT EFV PROGRAM WOULD NOT HAVE PREVENTED THE 6/9/93 ACCIDENT, BUT HAD AN EFV BEEN IN THE SERVICE LINE AT THE TIME OF THE ACCIDENT, IT SHOULD HAVE ACTIVATED, THEREBY MINIMIZING POTENTIAL LOSSES. THE NJNG'S NEW POLICY ON INSTALLING EFVS IS CONSISTENT WITH THE RECOMMENDED ACTION, & P-94-3 IS, THEREFORE, CLASSIFIED \"CLOSED--ACCEPTED ACTION.\"" }, { "addresseeAcronym": "NJNG", "addresseeOrganizationType": "P-Private Industry", "isFromNtsb": false, "communicationDate": "1995-06-07", "communicationType": "Official Correspondence", "communicationContents": "NJNG COMPLETED PHASE-IN THE EFV PROGRAM IN APRIL, 1995. NJNG INSTALLS EXCESS FLOW VALVES ON ALL NEW & RENEWED HIGH PRESSURE RESIDENTIAL GAS SYSTEMS SERVICE OPERATING AT A PRESSURE GREATER THAN 10M PSIG. EXCESS FLOW VALVES WILL NOT BE INSTALLED ON RESIDENTIAL SERVICES OPERATING AT A VOLUME IN EXCESS OF 400 CFH. NJNG HAS REVISED ITS CONSTRUCTION (STANDARDS) MANUAL TO INCORPORATE THIS PROVISION. WHILE NJNG BELIEVES THAT INSTALLING EXCESS FLOW VALVES ENHANCES THE SAFETY OF OUR SYSTEM, THIS PROGRAM WOULD NOT HAVE PREVENTED THE EXPLOSION AT 634 CLIFFWOOD AVENUE ON 6/9/93. THE EXISTENCE OF THE LINE DAMAGED THAT DAY WAS NOT KNOWN TO NJNG. IT IS MOST LIKELY THAT THE LINE WAS INSTALLED BEFORE WE PURCHASED THE FRANCHISE IN THAT AREA AND BEFORE EXCESS FLOW VALVES WERE IN GENERAL USE." } ] } ], "jurisdiction": "US" } ```